It is a known procedure from German patent application DE 10 2004 046 051 A1 to use an intelligent document to provide postage indicia generated in a central server to an operating unit via a network. Intelligent documents contain not only text elements and graphic elements but also a process logic that makes it possible to change the content of the document and to carry out prescribed processes. In particular, in this prior-art method, the printing of a postage indicium contained in such an intelligent document is logged in a central database and, before the printing procedure, it is ascertained whether this postage indicium has already been printed out before. If this is the case, the printing is not permitted, thereby preventing multiple printing of the postage indicium with fraudulent intent. The logging of the printing and the checking steps are carried out by means of the process logic of the intelligent document, said process logic controlling especially the communication between the operating unit the central database. In order to execute the process logic, a program execution environment is needed that is contained in a display program that is executed in the operating unit of the customer and that is configured in such a way that it can display and interpret regular documents as well as intelligent documents. An example of such a display program is “Adobe Reader” made by the Adobe Company, whose more recent versions can process conventional PDF documents (PDF: Portable Document Format) as well as intelligent PDF documents.